Stuffing box



Patented Oct. 29, 1946 UNITED STATES i' PATENT OFFICE STUFFING Box Y Robert B. Kinzbach, Houston, Tex. Application January 10, 1944, serial No. 517,739

(c1. 2st-3s) 2 Claims.

rod has a side swaying, or swinging, movement as it reciprocates. It is one of the princip-al objects of the present invention to provide a stuffing box of the character described which is so constructed that it will accommodate itself to this side swaying movement of the rod so as to minimixe the Wear on the rod and at the Sametime maintain a fluid tight seal about the rod.

Another object of the invention is to provide a stuing box that may be packed, or repacked, without disassembling and while the rod is in motion.

A further object of the invention is to provide a stuling box of the character described that is of very simple construction and may be cheaply produced and readily assembled or dismantled.

With the above and other objects in view the invention has particular relation to certain novel features of construction, operation and arrangement of parts an example of which is given in this specication and illustrated in the accompanying drawing wherein:

Figure 1 shows a side elevation of a stufiing box installed and shown partly in section.

Figure 2 shows a plan view showing the polish rod in section.

Figure 3 shows a cross sectional view taken on the line 3--3 of Figure 1.

Figure 4 shows a vertical, sectional view of another embodiment of the invention.

Figure 5 shows a cross sectional View taken on the line 5-5 of Figure 4, and

Figure 6 shows a side view, partly in section of a reserve supply packing cylinder.

Referring now more particularly to the drawing wherein like numerals of reference designate the same parts in each of the figures the numeral I designates the housing whose lower end is reduced and outwardly threaded to be screwed into the upper end of the well tubing 2. This housing has a top Ia connected to the body I of the housing by suitable threads.

tainer ring 3 for retaining the packing. The ring has the radial external spacers 4 to hold it approximately centered in the housing.

As is clearly shown in Figure 1 the housing is of a` general tubular form so as to admit the .polish rod 5 which reciprocates verticallytherethrough. The minimum inside diameter of the rod passageway through the housing is considerably greater than the maximum transverse diameter of the rod so as to allow the required range of lateral movement of the rod relative to the housing, as the. rod reciprocates.

The housing has the inside annular depending upper boss 6 and the inside annularupstanding lower boss 'I therein. There are the upper and lower floating plates 8 and 9 fitted against these respective bosses and having central bearings through which the rod 5 fits snugly. These plates move laterally with the rod as it sways during its up and down movements.

Fitted snugly within the ring 3 are the upper and lower retaining rings I0 and Il. Interposed between the rings ID and II there is a coil spring I2 which holds the rings I0 and II against the respective plates 8 and 9. The rings I0 and II are iitted snugly within, and have a ground fit with, the ring 3 and the plates 8 and 9 also have ground fits with the bosses 6 and 1 as well as with the rings I El and Il.

As is obvious there is a closed packing chamber within the ring 3 which is closed by the plates and 9 and the rings Ill and II. This chamber is completely fitted with -a plastic packing I3 which forms a seal with the rod.

In order to ll the chamber with packing there is an inlet passageway I 4, through one of the bosses of the ring 3 and a tubular nipple I5 extends through a radial opening in the housing and is equipped with a back pressure valve I6, normally closed by the plug ll. This plug may be removed and packing forced into the packing chamber by a suitable gun, provided for the purpose and additional packing may be supplied from time to time should the stuffing box develop a leak.

In the form shown in Figure 4 the housing Ib is substantially similar to the housing shown in Figure l. However within the housing and sup- "ported on the lower boss 'I there is an open work Within the housing there is a cylindrical recage i8 consisting of the upper and lower plates I9 and 2li, connected by the vertical bars 2| which are spaced apart. The plates i9 and 2B have the central bearings through which the rod 5 works.

' Screwed into the upper end of the cage Ib there Vis a cap Ic having an enlarged central passageway to receive the rod and this cap lc is externally threaded to be screwed into and close the upper end of the housing. It may be screwed down tightly against the cage to hold the cage centered and against lateral movement or it may be relaxed to permit lateral movement of the cage.

The cage is of an external transverse diameter somewhat. less than the maximum internal diameter of thehousing as'shown.

The plastic packing material may be forced into the housing Ib as above explained until it fills the housing both around and within the cage so as to form a seal about the rod 5.

It may be found desirable to provide means for constantly supplying additional packing to the chamber to replace the loss from wear. For this reason a cylinder 22 has been provided which may be substituted for the nipple I5. This cylinder contains the chamber 23 for a reserve supply of packing and a plunger 24, in the cylinder is held against the packing by a strong coil spring 25. A plug 26 is screwed into the outer end of the cylinder against said spring. to place the spring under-.the required compression. A stem 21v is attached to the plunger and extends out through an axial bearing in the plug 26.

As the packing is displaced from the packing chamber, additionalpacking will be constantly forced. into the chamber from the cylinder 22. TheU outer end of the rod 27 serves as a gauge to indicate when the reserve supply is low. When 4 necessary the plug 26 and plunger 24 may be removed and an additional reserve supply of packing placed in the cylinder and the plunger and plug then replaced as shown in Figure 6.

What I claim is:

1. A stuffing box comprising, a housing having a rod passageway and an internal chamber, a rod sealing assembly in the chamber including an internal rigid cage having upper and lower rodbearings andv also having an internal chamber, sealing means filling both chambers and forming a seal around the rod through the stuffing box, the ends of the cage sealing said rod passageway, around the rod, at the top and bottom of the housing chamber, said assembly being laterally movable, with the rod in the housing.

2. A- stuimg box comprising, a housing having a rod passageway and an internal chamber, a rod sealing assembly in the chamber including a rigid cage having upper and lower rod-bearings and also having an internal chamber, sealing means filling both chambers and forming a seal around the rod through the stufling box, the ends of the cage sealing said rod passageway, around the rod, at the top and bottom of the housing chamber, said assembly being laterally movable, with the rod in the housing and a clamp nut at one end of the housing forming means for clamping the assembly against movement relative to the housing.

ROBERT B. KINZBACH. 

